Means for operating looms



' March 6, 1956 P. w. MEYER 2,731,209

MEANS FOR OPERATING LOOMS Filed Nov. 3 1951 2 Sheets-Sheet l INVENTORPETER W. MEYER ATTORNEY March 6, 1956 w, MEYER 2,737,209

MEANS FOR OPERATING LOOMS 5O as TO HIGH PRESSURE sounoe f' 7& 82 T1] T0LOW PRESSURE SOURCE 60 PETER W. MEYER 54 BY 7o 66 WM ATTORNEY UnitedStates Patent MEANS FOR OPERATING LOOMS Peter W. Meyer, Clemson, S. C.,assignor, by mesne assiguments, to Deering Milliken ResearchCorporation, Pendleton, S. C., a corporation of Delaware ApplicationNovember 3, 1951, Serial No. 254,701

Claims. (Cl. 139100) The present invention relates to looms andcomprises a novel method and means for eliminating or reducing thenumber and severity of set-marks. Set-mar is the name given toirregularities in filling spacing which occur when a loom has beenstopped and then later started up again, these irregularities showing upin the Woven fabric, particularly after dyeing and finishing, asfillingwise bands. In general, the longer the time during which a loomhas stopped, the more severe or pronounced is the set-mark.

Although various attempts have been made in the past to avoid theoccurrence of set-marks, none has heretofore proven successful so thatthe usual practice is to attack the problem from the other end, that is,to devise ways and means to prevent stopping of a loom during theweaving of the desired length of fabric. It is not always feasibleeconomically to operate a loom twentyfour hours a day and seven days aweek, and furthermore it is not possible to avoid at least occasionalstoppage of a loom, as for example when a warp or filling yarn breaks,or when mechanical failure of a part occurs.

It is an object of the present invention, therefore, to provide a methodof so operating a loom that set-marks in the fabric being woven eitherdo not occur upon.

loom stoppage or are so faint they do not cause the fabric to beclassified as seconds.

It is a further object of the invention to provide for looms of standardmanufacture an attachment which will not interfere with the weavingoperation and which will tend to prevent the occurrence of a set-mark inthe fabric when the loom is started up after it has been stopped.

Extensive experimentation leading to the development of the presentinvention revealed that the marks have their origin in a backwardsmovement of the fell, unless the loom is stopped with the reed in thefront dead center position, and that this movement is caused byrelaxation of the section of cloth between the guide rod or bar on thebreast beam and the fell. By reducing the tension on the warp from 40 to60% while the loom is stopped, and then returning it to its former valuewhen the loom is started up again or shortly thereafter, depending uponthe duration of the stopping period, backwards movement of the fell isprevented and stop, start and set-marks are minimized or entirelyeliminated. The present invention comprises this novel method ofreducing or eliminating set-marks and novel means for practicing thesame, of which three embodiments are diagrammatically illustrated in thedrawings.

Figs. 1 and 2 illustrate the invention as applied to a loom of the typewherein tension is applied to the warp by weights opposing rotation ofthe warp beam, Fig. 1 being a side view of the let-off end of theloom'and Fig. 2 being a side view of the right hand loomside; Fig. la isa fragmentary view illustrating an alternative tension relief device forthe loom of Figs. 1 and 2; Fig. 2a is a diagrammatic sectional view ofan enlarged scale of the control valve of Fig. 2; Figs. 3 and 4illustrate the for an understanding of the invention.

2,737,209 Patented Mar. 6, 1956 invention as applied to a loom of thetype having a ratchet driven let-off, Fig. 3 being a side view of thelet off end of the loom and Fig. 4 being a side view of the left handloomside of the loom at the breast beam.

In Figs. 1 and 2 the invention is illustrated as applied to a Cromptonand Knowles loom of the S type and as these looms are well known only somuch of the operating mechanism of the loom is illustrated as isnecessary In the type of loom illustrated, tension is applied to thewarp W by means of weights 2 which are cerried by a weight spindle 4depending from the free end of a weight support arm 6. The other end ofweight support arm 6 is connected to a casing 8 of the let-off mechanismfor the warp beam. For a detailed description of the operating elementsof the let-off mechanism reference may be had to U. S. Patent No.1,803,143 to O. V. Payne dated April 28, 1931. In general, however, theweights 2 exert a torque on the warp beam to tension the warp yarns. Inaccordance with the invention, a pneumatic jack 10 is located directlybeneath the lower end of the weight spindle rod 4. The platform 12 ofthe jack is attached to the piston 14 disposed within the cylinder 16 ofthe jack. Application of compressed air to the cylinder 16 through anair line 18 raises the piston and platform against the action of asuitable compression spring. The stroke of the piston rod 20 upon whichthe platform 12 is mounted is so adjusted that the platform engages thelower end of the spindle rod 4 when near the completion of its upstroke"and relieves the force exerted by the weights upon the arm 6 to apredetermined extent. Thus when the jack 10 is actuated, it serves toexert a countertorque on the Warp beam to relieve by a predeterminedamount, the tension in the warp yarns.

Attached to the frame 22 of the loom adjacent the shipper handle 24 is athree way air plunger type valve 26 which in one position, thatillustrated in Figs. 2 and 2a, connects line 18 to a compressed air line28 and in the other position, to the left as viewed in Figs. 2 and 2a,connects line 18 to an exhaust port 30. A resilient bumper 32 of rubber,or the like, is secured to the lever 34 operated by the shipper handle24 and the valve 26 is so mounted as to present the end of the plunger36 thereof to the bumper 32 to be moved thereby into the first mentionadposition when the shipper handle is rocked to the loom stopped positionillustrated in Fig. 2. A compression spring 38, acting on the other endof the plunger 36, moves the plunger into position to connect line 18with the exhaust port 30 when the shipper handle is moved to loomrunning position. In order that the valve may be prevented, if desired,from moving to this latter position when the loom is started up, asolenoid 4i), energization of which is controlled by a manually operableswitch 42, is positioned adjacent the end of the plunger 36 remote fromthe bumper 32 and the movable core thereof is secured to the plunger soas to move the plunger against the action of spring 38 when the solenoidis energized.

The operation of the above described apparatus is as follows: Wheneverthe loom is stopped, either by the op erator or by the automatic stopmechanism of the loom, the shipper handle 24 moves through a fixed arcof rotation, so that the bumper on lever 34 engages the piston plunger36 and moves it into the position connecting lines 18 and 28. Compressedair from line 28 flows through the line 18 into the cylinder 16 of thejack 10, thus elevating the platform 12 and bringing it into contactwith the lower end of the weight spindle rod 4. The effective weight onthe arm 6 is thus reduced, lessening the tension upon the warp yarns.Preferably the air pressure is so 3 adiusted thatv the tension upon thewarp is reduced from to 60%.

In order to start up the loom again, the operator simply moves theshipper handle 24 to the on position. This releases the piston plunger36, thus permitting air to exhaust from the cylinder 16 through the line18 and exhaust port 3d. The platform 12 is thus lowered, and the tensionapplied to the warp W is returned to its original value under the forceof the weights 2.

If the loom has been stopped for long periods of the operator firstturns the switch 42 to the on position to energize the solenoid 4i), andthen he starts the loom in the customary manner, permitting it to makeseveral picks. During this time, the piston plunger 36 is held by thesolenoid 40 and does not return to its original position, so that thetension upon the warp remains reduced. After a few picks have beencompleted, the operator then turns the switch 42 to the elf positiondeenergizing solenoid 4i! and permiting plunger 36 to return to theposition wherein air exhausts through the line 18 and. exhaust port 39and the original tension is again applied to the warp. This delayedapplication of tension to the warp is advisable in order to preventoccurrence of set-marks when the loom has been stopped for long periodsof time such as over 24 hours or a week end.

Figs. 3 and 4 show portions of a Draper loom equipped with tensionrelief means embodying the invention. In this type of a loom a ratchetwheel controlling rotation of the Warp beam is intermittently rotatedthrough a few degrees by means coupled to the reciprocating parts of theloom. These coupling means are operatively connected with the whip rollto permit the tension in the warp acting; through the whip roll tocontrol the amount of rotation of the ratchet wheel. In Fig. 3 theratchet wheel is indicated at 44, the connecting rod for operating thedriving pallet for the wheel 4 at 46, the connecting rod collar at 47,the driving rod for reciprocating the connecting rod at 48, the whiproll at 50, whip roll lever at 52 and the upright lever, normallycoupling the connecting rod 46 to the whip roll lever 52 through avibrating 4 rod assembly, at 54. In accordance with the invention an aircylinder 56 having a piston and tie rod 60 is interposed between thewhip roll lever 52 and the upright lever 54 with its tie rod 60pivotally connected at one end to the lower end of the whip roll lever52 and at its other end to the upright lever 54. The pressure chamber 62of the cylinder is connected through a nipple 64 to a hose 66 the otherend of which (see Fig. 4) is connected to a plunger type three way valve68 mounted on the frame 70 of the loom adjacent the shipper handle 72, agauge 74 and pressure relief valve 76 being interposed in the line 66between the cylinder and the valve. The valve 68 has a piston plunger 78therein provided with passages which in one position, that shown in Fig.4, connect line 66 with a low pressure line fill and in a secondposition connect line 66 with a high pressure line 82. Lines 80 and 82can be supplied with compressed air from different sources, or, as willbe readily apparent to those skilled in the art, a single high pressuresource may be provided. When a single source is employed, suitablepressure reducing valves (not shown) would be provided in the lines anda suitable pressure relief valve would be included in line 80 to insurereduction of the pressure in chamber 62 of the air cylinder 56 when theplunger of valve 68 is moved into position to connect lines 66 and 80. Aspring 84 biases the plunger to the position wherein line 66 isconnected to the high pressure line 82 which position is assumed by thevalve While the loom is operating. A flat spring 86 secured to the shaftof the shipper handle 72 engages the end of the plunger 78 remote fromspring 84 when the shipper handle is in loom stopping position and holdsthe plunger in the first mentioned position wherein air under reducedpressure is supplied by air cylinder 56.

As in the embodiment of the invention illustrated in Figs. 1 and 2 asolenoid 88, energization of which is controlled by a manually operatedswitch 90, is positioned adjacent the end of the plunger 73 and themovable core thereof is secured to the plunger so as to hold the plungeragainst the action of spring 84 when the solenoid is energized.

The operation of this device is as follows: When the shipper handle 72is turned to the loom stopped position, plunger 78 is forced againstspring 84 and the line no is connected to the compressed air line ofreduced pressure, reducing the pressure in the chamber 62 of thecylinder 56. The piston 58 and tie rod 60 are therefore moved to theright, as viewed in Fig. 3, under the tension of the warp exerted on thewhip roll. The stroke of the piston is so adjusted by regulation of theair pressure that the tension on the warp is thus reduced from 40 to60%. When the shipper handle 72 is moved in the direction of the arrowinto loom operating position, compressed air under high pressure issupplied to line 66 and piston 58 moves rearwardly rocking the whip rolllever and returning the tension of the warp to its former value. As inthe embodiment of the invention illustrated in Figs. 1 and 2, theoperator by manipulation of switch 9%; may delay the application of warptension.

The above described tension relief means of Figs. 3 and 4 does notinterfere with the normal operation of the letolfi mechanism of theloom. Excess tension in the Warp acts through the whip roll, whip rolllever and tie rod to rock the upright lever 54 which shifts theconnecting collar 47 thus allowing the ratchet wheel 44 to be operatedin the direction to let oii warp and thereby reduce tension therein. Itis only when the loom is stopped that the tension relief means of theinvention comes into operation as heretofore described.

In Fig. la is indicated an alternative means for relieving warp tensionin a Crornpton and Knowles S type loom. In this embodiment of theinvention the weights are replaced by an air cylinder controlledsimilarly to cylinder 55 in Figs. 3 and 4. The arm 6 of. the let-oilmechanism is connected directly to the piston red as of an air cylinder56'. The cylinder 56', above the piston 55%, is supplied with compressedair through a line 65 from any suitable source (not shown). The cylinderbelow the piston 58' is connected to atmosphere, or if desired, to asource of compressed air under reduced pressure. It will be understoodthat the pressure in line as can be controlled in response to theposition of the shipper handle in the same manner as that described forline 66 of Figs. 3 and 4, the pressure being high during operation ofthe loom and being reduced during loom stoppage. If desired a four waycontrol valve may be employed and the cylinder 56' below the piston 58'connected thereto so that, by proper adjustment of air pressure appliedto opposite sides of the piston, its position, and thus the tensionapplied to the warp, can be accurately regulated.

The invention has now been described with particular reference to twodifferent types of looms. Although in each embodiment of the inventionpneumatically operated means for reducing warp tension during loomstoppage have been illustrated, obviously hydraulic or electricallyoperated means could be substituted therefor and various other changesin the particular constructions illustrated and described could be madewithout departing from the spirit of the invention or the scope of theaccompanying claims.

The following is offered as a possible explanation for the function. ofthe apparatus of the invention in preventing set-marks, but is given forinformation only and the scope. of the invention is not to be limitedthereby: It is believed that when the loom is not operating and thecloth is subjected to the tension applied to the Warp necessary forproper weaving, the cloth tends to stretch, thus moving the fell backtowards the Warp beam unless prevented from doing so by the front centerposition of the reed. Apparently, little or no stretch takes place inthe Warp itself, all of the dimensional changes occurring in the cloth.Because the fell has moved backwards, for the first few picks after theloom is started up again, the newly-placed filling yarns are heat uprelatively close to each other thus creating a set-mark. After a fewpicks, however, the fell returns to its original equilibrium position,and thereafter picks are the proper distance apart in the newly wovencloth. The apparatus of the present invention overcomes this problem byrelieving the tension applied to the cloth, while the loom is stationaryso that the fell does not change its position, and yet permitsreapplication of tension to the degree originally obtained upon startingup the loom or shortly thereafter, as desired.

The following is claimed:

1. In a let-ofl mechanism for a loom having a warp beam delivering warpand means to retain said warp under tension during loom operationcomprising a whiproll associated with said warp beam, means cooperatingwith said tension applying means for relieving the tension appliedthereby while said loom is stopped, said tensionrelieving meanscomprising a cylinder, a fluid pressureactuated piston disposed therein,a piston rod affixed to said piston and operatively associated with saidwhip-roll, and means for applying fluid pressure to said piston toactuate said piston rod and thereby adjust the tension applied to thewarp by the whip-roll.

2. An apparatus for preventing the occurrence of setmarks in aloom-woven fabric, which comprises, in a loom having a warp beamdelivering Warp, means for starting and stopping said loom, means forapplying tension to a warp, and, associated with said tension-applyingmeans, means for cooperating therewith to reduce the tension appliedthereby, comprising a cylinder, a fluid pressure-actuated pistondisposed therein, means for applying fluid pressure to said piston,means associated with said loom stopping and starting means foractuating said fluid pressure-applying means simultaneously withstopping the loom, and means associated with said last-mentioned meansfor preventing deactuation thereof when the loom is neXt started up.

3. An apparatus for preventing the occurrence of setmarks in aloom-woven fabric, which comprises, in a loom having a warp beamdelivering warp, means for starting and stopping said loom, means forapplying tension to a warp, and, associated with said tension-applyingmeans, means cooperating therewith to reduce the tension appliedthereby, comprising a cylinder, a fluid-pressure-actuated pistondisposed therein, and means for applying fluid pressure to said piston,means associated with said loom starting and stopping means foractuating said fluid pressure-applying means, comprising a three-wayvalve, a spring-loaded reciprocable piston plunger disposed therein forconnecting two of three passages therein at one time, one end of saidpiston plunger being engaged and reciprocated by said loom-control meansagainst the thrust of said spring, an electric solenoid disposedadjacent said valve for receiving the other end of said plunger, andpreventing reciprocation thereof when electrically actuated, and switchmeans for controlling actuation of said solenoid.

4. In a loom having a warp beam delivering warp, means for applying atorque to the beam to place the warp under tension, and means includinga shipper handle movable to operative and inoperative positions forstart- 6 ing and stopping the loom, said torque applying means includinga lever associated with said beam, means dependent from said lever forsupporting weights to control the tension applied by said lever andhaving weights disposed thereon, and tension relieving means comprisinga cylinder having a reciprocable fluid pressure actuated piston disposedtherein, a piston rod afiixed to said piston, said piston rod onactuation of said piston being engageable with said weight-supportingmeans to relieve the force exerted upon said lever by said weights, andmeans operable in response to movement of said shipper lever toinoperative position for applying fluid pressure to said 'piston toactuate the same.

5. The improvement in accordance with claim 4 including means formaintaining the fluid pressure on said piston for a selected time periodfollowing movement of said shipper handle to the operative positionwhereby the restoration of normal tension on said warp is delayed duringsaid time period.

6. In a loom having a warp beam delivering warp, means for applying atorque to the beams to place the warp under tension, and means movableto operative and inoperative positions for starting and stopping theloom, the improvement comprising means operative in response to movementof said movable means to inoperative position for applying acountertorque to said beam to reduce the tension in said warp when theloom is stopped.

7. The improvement according to claim 6 including means for maintainingsaid third mentioned means in its countertorque applying position.

8. The improvement according to claim 6 wherein the means for applying acountertorque to the beam comprises a fluid actuated motor to whichfluid under pressure is controlled by a valve actuated in accordancewith movement of said movable means for starting and stopping the loom.

9. The improvement according to claim 8 including means for selectivecontrolling said valve to maintain fluid under pressure at said motorindependently of the movement of the movable means to a loom startingposition.

10. The improvement according to claim 9 wherein said valve has amovable control member adapted to be actuated to open position by saidmovable means on movement to loom stopping position, means for biasingsaid movable control member to closed position, an electric solenoidoperatively coupled to said movable control member, and switch means forcontrolling the energization of the solenoid whereby said valve may beheld open at will against the action of said biasing means followingmovement of said movable means to loom starting position.

References Cited in the file of this patent UNITED STATES PATENTS710,024 Stimpson Sept. 30, 1902 781,681 Roper Feb. 7, 1905 843,181 RoperFeb. 5, 1907 1,643,412 Lane Sept. 27, 1927 2,526,303 Turner Oct. 17,1950 2,551,920 Willis May 8, 1951 2,571,509 Willis Oct. 16, 19512,571,510 Willis Oct. 16, 1951

